Vitamin B6

What is it?

Vitamin B6 is a water-soluble compound that was discovered in the 1930s during nutrition studies on rats. It was named pyridoxine to indicate its structural homology to
pyridine. Later it was shown that it could exist in two other, slightly different, chemical forms, termed pyridoxal and pyridoxamine. All three forms of the supplement are precursors of an activated compound known as pyridoxal 5'-phosphate (PLP), which play a vital role as the cofactor of a large number of essential enzymes in the human body.

Enzymes dependent on PLP focus a wide variety of chemical reactions mainly involving amino acids. The reactions carried out by the PLP-dependent enzymes that act on amino acids include transfer of the amino group, decarboxylation, racemization, and beta- or gamma-elimination or replacement. Such versatility arises from the ability of PLP to covalently bind the substrate, and then to act as an electrophilic catalyst, thereby stabilizing different types of carbanionic reaction intermediates.